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AdamGL

OpenGL TGA fiiles

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Sorry, I just can't seem to get it. I have Beginning OpenGL Game programming the book, but I can't seem to grasp the TGA loading part. Can anyone post a simple bit of code that loads a tga, with no linked lists. I would appreciate it. And if you could explain each part and what it does. I'm a newbie so please don't slap me for asking this. Adam L

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If you need some TGA loading code I have a nice class that handles everything you need. So if you want it I'll give it to you.

Jake

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Sure jake_Ghost, if you wouldn't mind also including descriptions of what certain things do in it that would be great!

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Alight if you guys could help me debug that would be great. What happens is I get a bunch of verical bars. Multicolored bars. Hippi bars. Anyways, I'll post the code. Its long so bear with me please.

tga.h

#include <windows.h> // Standard Windows header
#include <stdio.h> // Standard Header For File I/O
#include <gl\gl.h> // Standard Header For OpenGL
#include <gl\glu.h>

typedef struct
{
GLubyte* imageData; // Hold All The Color Values For The Image.
GLuint bpp; // Hold The Number Of Bits Per Pixel.
GLuint width; // The Width Of The Entire Image.
GLuint height; // The Height Of The Entire Image.
GLuint texID; // Texture ID For Use With glBindTexture.
GLuint type; // Data Stored In * ImageData (GL_RGB Or GL_RGBA)
} Texture;

typedef struct
{
GLubyte Header[12]; // File Header To Determine File Type
} TGAHeader;

typedef struct
{
GLubyte header[6]; // Holds The First 6 Useful Bytes Of The File
GLuint bytesPerPixel; // Number Of BYTES Per Pixel (3 Or 4)
GLuint imageSize; // Amount Of Memory Needed To Hold The Image
GLuint type; // The Type Of Image, GL_RGB Or GL_RGBA
GLuint Height; // Height Of Image
GLuint Width; // Width Of Image
GLuint Bpp; // Number Of BITS Per Pixel (24 Or 32)
} TGA;

TGAHeader tgaheader; // Used To Store Our File Header
TGA tga; // Used To Store File Information

// Uncompressed TGA Header
GLubyte uTGAcompare[12] = {0,0, 2,0,0,0,0,0,0,0,0,0};
// Compressed TGA Header
GLubyte cTGAcompare[12] = {0,0,10,0,0,0,0,0,0,0,0,0};

// Load An Uncompressed File
bool LoadUncompressedTGA(Texture *, char *, FILE *);
// Load A Compressed File
bool LoadCompressedTGA(Texture *, char *, FILE *);

//load a tga file
bool LoadTGA(Texture * texture, char * filename)
{
FILE * fTGA; // Declare File Pointer
fTGA = fopen(filename, "rb"); // Open File For Reading

if(fTGA == NULL) // If Here Was An Error
{

return false; // Return False
}

if(fread(&tgaheader, sizeof(TGAHeader), 1, fTGA) == 0)
{

return false; // Return False If It Fails
}

// If The File Header Matches The Uncompressed Header
if(memcmp(uTGAcompare, &tgaheader, sizeof(tgaheader)) == 0)
{
// Load An Uncompressed TGA
LoadUncompressedTGA(texture, filename, fTGA);
}
// If The File Header Matches The Compressed Header
else if(memcmp(cTGAcompare, &tgaheader, sizeof(tgaheader)) == 0)
{
// Load A Compressed TGA
LoadCompressedTGA(texture, filename, fTGA);
}
else // If It Doesn't Match Either One
{
fclose(fTGA);
return false; // Return False
}
}

// Load An Uncompressed TGA!
bool LoadUncompressedTGA(Texture * texture, char * filename, FILE * fTGA)
{
// Attempt To Read Next 6 Bytes
if(fread(tga.header, sizeof(tga.header), 1, fTGA) == 0)
{

return false; // Return False
}

texture->width = tga.header[1] * 256 + tga.header[0]; // Calculate Height
texture->height = tga.header[3] * 256 + tga.header[2]; // Calculate The Width
texture->bpp = tga.header[4]; // Calculate Bits Per Pixel
tga.Width = texture->width; // Copy Width Into Local Structure
tga.Height = texture->height; // Copy Height Into Local Structure
tga.Bpp = texture->bpp; // Copy Bpp Into Local Structure

// Make Sure All Information Is Valid
if((texture->width <= 0) || (texture->height <= 0) || ((texture->bpp != 24) && (texture->bpp !=32)))
{

return false; // Return False
}

if(texture->bpp == 24) // Is It A 24bpp Image?
texture->type = GL_RGB; // If So, Set Type To GL_RGB
else // If It's Not 24, It Must Be 32
texture->type = GL_RGBA; // So Set The Type To GL_RGBA

tga.bytesPerPixel = (tga.Bpp / 8); // Calculate The BYTES Per Pixel
// Calculate Memory Needed To Store Image
tga.imageSize = (tga.bytesPerPixel * tga.Width * tga.Height);

// Allocate Memory
texture->imageData = (GLubyte *)malloc(tga.imageSize);
if(texture->imageData == NULL) // Make Sure It Was Allocated Ok
{

return false; // If Not, Return False
}

// Attempt To Read All The Image Data
if(fread(texture->imageData, 1, tga.imageSize, fTGA) != tga.imageSize)
{

return false; // If We Cant, Return False
}

// Start The Loop
for(GLuint cswap = 0; cswap < (int)tga.imageSize; cswap += tga.bytesPerPixel)
{
// 1st Byte XOR 3rd Byte XOR 1st Byte XOR 3rd Byte
texture->imageData[cswap] ^= texture->imageData[cswap+2] ^=
texture->imageData[cswap] ^= texture->imageData[cswap+2];
}

fclose(fTGA); // Close The File
return true; // Return Success
}

bool LoadCompressedTGA(Texture * texture, char * filename, FILE * fTGA)
{
if(fread(tga.header, sizeof(tga.header), 1, fTGA) == 0) // Attempt to read header
{
MessageBox(NULL, "Could not read info header", "ERROR", MB_OK); // Display Error
if(fTGA != NULL) // If file is open
{
fclose(fTGA); // Close it
}
return false; // Return failed
}

texture->width = tga.header[1] * 256 + tga.header[0]; // Determine The TGA Width (highbyte*256+lowbyte)
texture->height = tga.header[3] * 256 + tga.header[2]; // Determine The TGA Height (highbyte*256+lowbyte)
texture->bpp = tga.header[4]; // Determine Bits Per Pixel
tga.Width = texture->width; // Copy width to local structure
tga.Height = texture->height; // Copy width to local structure
tga.Bpp = texture->bpp; // Copy width to local structure

if((texture->width <= 0) || (texture->height <= 0) || ((texture->bpp != 24) && (texture->bpp !=32))) //Make sure all texture info is ok
{
MessageBox(NULL, "Invalid texture information", "ERROR", MB_OK); // If it isnt...Display error
if(fTGA != NULL) // Check if file is open
{
fclose(fTGA); // Ifit is, close it
}
return false; // Return failed
}

tga.bytesPerPixel = (tga.Bpp / 8); // Compute BYTES per pixel
tga.imageSize = (tga.bytesPerPixel * tga.Width * tga.Height); // Compute amout of memory needed to store image
texture->imageData = (GLubyte *)malloc(tga.imageSize); // Allocate that much memory

if(texture->imageData == NULL) // If it wasnt allocated correctly..
{
MessageBox(NULL, "Could not allocate memory for image", "ERROR", MB_OK); // Display Error
fclose(fTGA); // Close file
return false; // Return failed
}

GLuint pixelcount = tga.Height * tga.Width; // Nuber of pixels in the image
GLuint currentpixel = 0; // Current pixel being read
GLuint currentbyte = 0; // Current byte
GLubyte * colorbuffer = (GLubyte *)malloc(tga.bytesPerPixel); // Storage for 1 pixel

do
{
GLubyte chunkheader = 0; // Storage for "chunk" header

if(fread(&chunkheader, sizeof(GLubyte), 1, fTGA) == 0) // Read in the 1 byte header
{
MessageBox(NULL, "Could not read RLE header", "ERROR", MB_OK); // Display Error
if(fTGA != NULL) // If file is open
{
fclose(fTGA); // Close file
}
if(texture->imageData != NULL) // If there is stored image data
{
free(texture->imageData); // Delete image data
}
return false; // Return failed
}

if(chunkheader < 128) // If the ehader is < 128, it means the that is the number of RAW color packets minus 1
{ // that follow the header
chunkheader++; // add 1 to get number of following color values
for(short counter = 0; counter < chunkheader; counter++) // Read RAW color values
{
if(fread(colorbuffer, 1, tga.bytesPerPixel, fTGA) != tga.bytesPerPixel) // Try to read 1 pixel
{
MessageBox(NULL, "Could not read image data", "ERROR", MB_OK); // IF we cant, display an error

if(fTGA != NULL) // See if file is open
{
fclose(fTGA); // If so, close file
}

if(colorbuffer != NULL) // See if colorbuffer has data in it
{
free(colorbuffer); // If so, delete it
}

if(texture->imageData != NULL) // See if there is stored Image data
{
free(texture->imageData); // If so, delete it too
}

return false; // Return failed
}
// write to memory
texture->imageData[currentbyte ] = colorbuffer[2]; // Flip R and B vcolor values around in the process
texture->imageData[currentbyte + 1 ] = colorbuffer[1];
texture->imageData[currentbyte + 2 ] = colorbuffer[0];

if(tga.bytesPerPixel == 4) // if its a 32 bpp image
{
texture->imageData[currentbyte + 3] = colorbuffer[3]; // copy the 4th byte
}

currentbyte += tga.bytesPerPixel; // Increase thecurrent byte by the number of bytes per pixel
currentpixel++; // Increase current pixel by 1

if(currentpixel > pixelcount) // Make sure we havent read too many pixels
{
MessageBox(NULL, "Too many pixels read", "ERROR", NULL); // if there is too many... Display an error!

if(fTGA != NULL) // If there is a file open
{
fclose(fTGA); // Close file
}

if(colorbuffer != NULL) // If there is data in colorbuffer
{
free(colorbuffer); // Delete it
}

if(texture->imageData != NULL) // If there is Image data
{
free(texture->imageData); // delete it
}

return false; // Return failed
}
}
}
else // chunkheader > 128 RLE data, next color reapeated chunkheader - 127 times
{
chunkheader -= 127; // Subteact 127 to get rid of the ID bit
if(fread(colorbuffer, 1, tga.bytesPerPixel, fTGA) != tga.bytesPerPixel) // Attempt to read following color values
{
MessageBox(NULL, "Could not read from file", "ERROR", MB_OK); // If attempt fails.. Display error (again)

if(fTGA != NULL) // If thereis a file open
{
fclose(fTGA); // Close it
}

if(colorbuffer != NULL) // If there is data in the colorbuffer
{
free(colorbuffer); // delete it
}

if(texture->imageData != NULL) // If thereis image data
{
free(texture->imageData); // delete it
}

return false; // return failed
}

for(short counter = 0; counter < chunkheader; counter++) // copy the color into the image data as many times as dictated
{ // by the header
texture->imageData[currentbyte ] = colorbuffer[2]; // switch R and B bytes areound while copying
texture->imageData[currentbyte + 1 ] = colorbuffer[1];
texture->imageData[currentbyte + 2 ] = colorbuffer[0];

if(tga.bytesPerPixel == 4) // If TGA images is 32 bpp
{
texture->imageData[currentbyte + 3] = colorbuffer[3]; // Copy 4th byte
}

currentbyte += tga.bytesPerPixel; // Increase current byte by the number of bytes per pixel
currentpixel++; // Increase pixel count by 1

if(currentpixel > pixelcount) // Make sure we havent written too many pixels
{
MessageBox(NULL, "Too many pixels read", "ERROR", NULL); // if there is too many... Display an error!

if(fTGA != NULL) // If there is a file open
{
fclose(fTGA); // Close file
}

if(colorbuffer != NULL) // If there is data in colorbuffer
{
free(colorbuffer); // Delete it
}

if(texture->imageData != NULL) // If there is Image data
{
free(texture->imageData); // delete it
}

return false; // Return failed
}
}
}
}

while(currentpixel < pixelcount); // Loop while there are still pixels left
fclose(fTGA); // Close the file
return true; // return success
}



Stuff to initialize once

Texture texture;
glEnable(GL_TEXTURE_2D); // Enable Texture Mapping ( NEW )
glShadeModel(GL_SMOOTH); // Enable Smooth Shading
glClearColor(0.0f, 0.0f, 0.0f, 0.5f); // Black Background
glClearDepth(1.0f); // Depth Buffer Setup
glEnable(GL_DEPTH_TEST); // Enables Depth Testing
glDepthFunc(GL_LEQUAL); // The Type Of Depth Testing To Do
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); // Really Nice Perspective Calculations
LoadTGA(&texture, "lightsaber.tga");

glGenTextures(1, &texture.texID); // Create The Texture
// Typical Texture Generation Using Data From The Bitmap
glBindTexture(GL_TEXTURE_2D, texture.texID);
glTexImage2D(GL_TEXTURE_2D, 0, 3, texture.width, texture.height, 0, GL_RGB, GL_UNSIGNED_BYTE, texture.imageData);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);



stuff in loop

glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear Screen And Depth Buffer
glLoadIdentity();
glBindTexture(GL_TEXTURE_2D, texture.texID);
glBegin(GL_QUADS);
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f); // Bottom Left Of The Texture and Quad
glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f); // Bottom Right Of The Texture and Quad
glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 1.0f); // Top Right Of The Texture and Quad
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f); // Top Left Of The Texture and Quad
glEnd();
SwapBuffers(hDC);



I'm not in a rush so take as long as you need to reply, if you reply at all. Sorry about all this.

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Quote:
Original post by AdamGL
What happens is I get a bunch of verical bars. Multicolored bars. Hippi bars.

Does the problem happen with all .tga textures you try, or just with some of them? More specifically... do you get the same effect with both uncompressed and compressed textures, or just with one of these types..?

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thanks man, that was a big waste of space up there. It shows up, the same type of tga uncompressed and 32 bit. How do I make a proper tga file. What aree my limitations?

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Wait, I found out why. My image was a 32 bit image. The others were 24 bit. Why can't I load the 32 bit one?

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    • By OneKaidou
      Hi
       
      I am trying to program shadow volumes and i stumbled upon an artifact which i can not find the cause for.
      I generate the shadow volumes using a geometry shader with reversed extrusion (projecting the lightfacing triangles to infinity) and write the stencil buffer according to z-fail. The base of my code is the "lighting" chapter from learnopengl.com, where i extended the shader class to include geometry shader. I also modified the "lightingshader" to draw the ambient pass when "pass" is set to true and the diffuse/ specular pass when set to false. For easier testing i added a view controls to switch on/off the shadow volumes' color rendering or to change the cubes' position, i made the lightnumber controllable and changed the diffuse pass to render green for easier visualization of my problem.
       
      The first picture shows the rendered scene for one point light, all cubes and the front cube's shadow volume is the only one created (intentional). Here, all is rendered as it should be with all lit areas green and all areas inside the shadow volume black (with the volume's sides blended over).

      If i now turn on the shadow volumes for all the other cubes, we get a bit of a mess, but its also obvious that some areas that were in shadow before are now erroneously lit (for example the first cube to the right from the originaly shadow volumed cube). From my testing the areas erroneously lit are the ones where more than one shadow volume marks the area as shadowed.

      To check if a wrong stencil buffer value caused this problem i decided to change the stencil function for the diffuse pass to only render if the stencil is equal to 2. As i repeated this approach with different values for the stencil function i found out that if i set the value equal to 1 or any other uneven value the lit and shadowed areas are inverted and if i set it to 0 or any other even value i get the results shown above.
      This lead me to believe that the value and thus the stencil buffer values may be clamped to [0,1] which would also explain the artifact, because twice in shadow would equal in no shadow at all, but from what i found on the internet and from what i tested with
      GLint stencilSize = 0; glGetFramebufferAttachmentParameteriv(GL_DRAW_FRAMEBUFFER, GL_STENCIL, GL_FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE, &stencilSize); my stencilsize is 8 bit, which should be values within [0,255].
      Does anyone know what might be the cause for this artifact or the confusing results with other stencil functions?
       
      // [the following code includes all used gl* functions, other parts are due to readability partialy excluded] // glfw: initialize and configure // ------------------------------ glfwInit(); glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4); glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 4); glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE); // glfw window creation // -------------------- GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", NULL, NULL); if (window == NULL) { cout << "Failed to create GLFW window" << endl; glfwTerminate(); return -1; } glfwMakeContextCurrent(window); glfwSetFramebufferSizeCallback(window, framebuffer_size_callback); glfwSetCursorPosCallback(window, mouse_callback); glfwSetScrollCallback(window, scroll_callback); // tell GLFW to capture our mouse glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED); // glad: load all OpenGL function pointers // --------------------------------------- if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress)) { cout << "Failed to initialize GLAD" << endl; return -1; } // ==================================================================================================== // window and functions are set up // ==================================================================================================== // configure global opengl state // ----------------------------- glEnable(GL_DEPTH_TEST); glEnable(GL_CULL_FACE); // build and compile our shader program [...] // set up vertex data (and buffer(s)) and configure vertex attributes [...] // shader configuration [...] // render loop // =========== while (!glfwWindowShouldClose(window)) { // input processing and fps calculation[...] // render // ------ glClearColor(0.1f, 0.1f, 0.1f, 1.0f); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glDepthMask(GL_TRUE); //enable depth writing glDepthFunc(GL_LEQUAL); //avoid z-fighting //draw ambient component into color and depth buffer view = camera.GetViewMatrix(); projection = glm::perspective(glm::radians(camera.Zoom), (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f); // setting up lighting shader for ambient pass [...] // render the cubes glBindVertexArray(cubeVAO); for (unsigned int i = 0; i < 10; i++) { //position cube [...] glDrawArrays(GL_TRIANGLES, 0, 36); } //------------------------------------------------------------------------------------------------------------------------ glDepthMask(GL_FALSE); //disable depth writing glEnable(GL_BLEND); glBlendFunc(GL_ONE, GL_ONE); //additive blending glEnable(GL_STENCIL_TEST); //setting up shadowShader and lightingShader [...] for (int light = 0; light < lightsused; light++) { glDepthFunc(GL_LESS); glClear(GL_STENCIL_BUFFER_BIT); //configure stencil ops for front- and backface to write according to z-fail glStencilOpSeparate(GL_FRONT, GL_KEEP, GL_DECR_WRAP, GL_KEEP); //-1 for front-facing glStencilOpSeparate(GL_BACK, GL_KEEP, GL_INCR_WRAP, GL_KEEP); //+1 for back-facing glStencilFunc(GL_ALWAYS, 0, GL_TRUE); //stencil test always passes if(hidevolumes) glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE); //disable writing to the color buffer glDisable(GL_CULL_FACE); glEnable(GL_DEPTH_CLAMP); //necessary to render SVs into infinity //draw SV------------------- shadowShader.use(); shadowShader.setInt("lightnr", light); int nr; if (onecaster) nr = 1; else nr = 10; for (int i = 0; i < nr; i++) { //position cube[...] glDrawArrays(GL_TRIANGLES, 0, 36); } //-------------------------- glDisable(GL_DEPTH_CLAMP); glEnable(GL_CULL_FACE); glStencilFunc(GL_EQUAL, 0, GL_TRUE); //stencil test passes for ==0 so only for non shadowed areas glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP); //keep stencil values for illumination glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE); //enable writing to the color buffer glDepthFunc(GL_LEQUAL); //avoid z-fighting //draw diffuse and specular pass lightingShader.use(); lightingShader.setInt("lightnr", light); // render the cubes for (unsigned int i = 0; i < 10; i++) { //position cube[...] glDrawArrays(GL_TRIANGLES, 0, 36); } } glDisable(GL_BLEND); glDepthMask(GL_TRUE); //enable depth writing glDisable(GL_STENCIL_TEST); //------------------------------------------------------------------------------------------------------------------------ // also draw the lamp object(s) [...] // glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.) // ------------------------------------------------------------------------------- glfwSwapBuffers(window); glfwP } // optional: de-allocate all resources once they've outlived their purpose: // ------------------------------------------------------------------------ glDeleteVertexArrays(1, &cubeVAO); glDeleteVertexArrays(1, &lightVAO); glDeleteBuffers(1, &VBO); // glfw: terminate, clearing all previously allocated GLFW resources. // ------------------------------------------------------------------ glfwTerminate(); return 0;  
    • By Green_Baron
      Hi,
      i am self teaching me graphics and oo programming and came upon this:
      My Window class creates an input handler instance, the glfw user pointer is redirected to that object and methods there do the input handling for keyboard and mouse. That works. Now as part of the input handling i have an orbiting camera that is controlled by mouse movement. GLFW_CURSOR_DISABLED is set as proposed in the glfw manual. The manual says that in this case the cursor is automagically reset to the window's center. But if i don't reset it manually with glfwSetCursorPos( center ) mouse values seem to add up until the scene is locked up.
      Here are some code snippets, mostly standard from tutorials:
      // EventHandler m_eventHandler = new EventHandler( this, glm::vec3( 0.0f, 5.0f, 0.0f ), glm::vec3( 0.0f, 1.0f, 0.0f ) ); glfwSetWindowUserPointer( m_window, m_eventHandler ); m_eventHandler->setCallbacks(); Creation of the input handler during window creation. For now, the camera is part of the input handler, hence the two vectors (position, up-vector).  In future i'll take that functionally out into an own class that inherits from the event handler.
      void EventHandler::setCallbacks() { glfwSetCursorPosCallback( m_window->getWindow(), cursorPosCallback ); glfwSetKeyCallback( m_window->getWindow(), keyCallback ); glfwSetScrollCallback( m_window->getWindow(), scrollCallback ); glfwSetMouseButtonCallback( m_window->getWindow(), mouseButtonCallback ); } Set callbacks in the input handler.
      // static void EventHandler::cursorPosCallback( GLFWwindow *w, double x, double y ) { EventHandler *c = reinterpret_cast<EventHandler *>( glfwGetWindowUserPointer( w ) ); c->onMouseMove( (float)x, (float)y ); } Example for the cursor pos callback redirection to a class method.
      // virtual void EventHandler::onMouseMove( float x, float y ) { if( x != 0 || y != 0 ) { // @todo cursor should be set automatically, according to doc if( m_window->isCursorDisabled() ) glfwSetCursorPos( m_window->getWindow(), m_center.x, m_center.y ); // switch up/down because its more intuitive m_yaw += m_mouseSensitivity * ( m_center.x - x ); m_pitch += m_mouseSensitivity * ( m_center.y - y ); // to avoid locking if( m_pitch > 89.0f ) m_pitch = 89.0f; if( m_pitch < -89.0f ) m_pitch = -89.0f; // Update Front, Right and Up Vectors updateCameraVectors(); } } // onMouseMove() Mouse movement processor method. The interesting part is the manual reset of the mouse position that made the thing work ...
      // straight line distance between the camera and look at point, here (0,0,0) float distance = glm::length( m_target - m_position ); // Calculate the camera position using the distance and angles float camX = distance * -std::sin( glm::radians( m_yaw ) ) * std::cos( glm::radians( m_pitch) ); float camY = distance * -std::sin( glm::radians( m_pitch) ); float camZ = -distance * std::cos( glm::radians( m_yaw ) ) * std::cos( glm::radians( m_pitch) ); // Set the camera position and perspective vectors m_position = glm::vec3( camX, camY, camZ ); m_front = glm::vec3( 0.0, 0.0, 0.0 ) - m_position; m_up = m_worldUp; m_right = glm::normalize( glm::cross( m_front, m_worldUp ) ); glm::lookAt( m_position, m_front, m_up ); Orbiting camera vectors calculation in updateCameraVectors().
      Now, for my understanding, as the glfw manual explicitly states that if cursor is disabled then it is reset to the center, but my code only works if it is reset manually, i fear i am doing something wrong. It is not world moving (only if there is a world to render :-)), but somehow i am curious what i am missing.
       
      I am not a professional programmer, just a hobbyist, so it may well be that i got something principally wrong :-)
      And thanks for any hints and so ...
       
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