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godkane

glDrawElements

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godkane    122
I'm trying to draw a simple cube. Currently this errors out because of the frontIndices looking wierd. private float[,] vertices = {{-1.0f, -1.0f, -1.0f}, { 1.0f, -1.0f, -1.0f}, { 1.0f, 1.0f, -1.0f}, { -1.0f, 1.0f, -1.0f}, {-1.0f, -1.0f, 1.0f}, { 1.0f, -1.0f, 1.0f}, { 1.0f, 1.0f, 1.0f}, { -1.0f, 1.0f, 1.0f}}; private float[,] colors = {{1.0f, 0.2f, 0.2f }, {0.2f, 0.2f, 1.0f }, {0.8f, 1.0f, 0.2f }, {0.75f, 0.75f, 0.75f}, {0.35f, 0.35f, 0.35f}, {0.5f, 0.5f, 0.5f }}; private Byte[,] frontIndices = {{0, 1, 2, 3}}; GL.glEnableClientState(GL.GL_COLOR_ARRAY); GL.glEnableClientState(GL.GL_VERTEX_ARRAY); GL.glColorPointer(3, GL.GL_FLOAT, 0, colors); GL.glVertexPointer(3, GL.GL_FLOAT, 0, vertices); GL.glDrawElements(GL.GL_QUADS, 1, GL.GL_BYTE, frontIndices);

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godkane    122
That is a minor issue when there is no lighting. Here is the same code but I know this works. I want to use the one that is much less code, plus should be faster too.(less commands) This is in C# if you couldn't tell. Currently when I run my code it is a black screen, so I'm not understanding how the equation is run with the data that I gave it. I'm reading this from a book that does this in C and everything looks right.
GL.glBegin(GL.GL_QUADS); // Draw A Quad

GL.glColor3f(0.0f,1.0f,0.0f); // Set The Color To Green
GL.glVertex3f( 1.0f, 1.0f,-1.0f); // Top Right Of The Quad (Top)
GL.glVertex3f(-1.0f, 1.0f,-1.0f); // Top Left Of The Quad (Top)
GL.glVertex3f(-1.0f, 1.0f, 1.0f); // Bottom Left Of The Quad (Top)
GL.glVertex3f( 1.0f, 1.0f, 1.0f); // Bottom Right Of The Quad (Top)

GL.glColor3f(1.0f,0.5f,0.0f); // Set The Color To Orange
GL.glVertex3f( 1.0f,-1.0f, 1.0f); // Top Right Of The Quad (Bottom)
GL.glVertex3f(-1.0f,-1.0f, 1.0f); // Top Left Of The Quad (Bottom)
GL.glVertex3f(-1.0f,-1.0f,-1.0f); // Bottom Left Of The Quad (Bottom)
GL.glVertex3f( 1.0f,-1.0f,-1.0f); // Bottom Right Of The Quad (Bottom)

GL.glColor3f(1.0f,0.0f,0.0f); // Set The Color To Red
GL.glVertex3f( 1.0f, 1.0f, 1.0f); // Top Right Of The Quad (Front)
GL.glVertex3f(-1.0f, 1.0f, 1.0f); // Top Left Of The Quad (Front)
GL.glVertex3f(-1.0f,-1.0f, 1.0f); // Bottom Left Of The Quad (Front)
GL.glVertex3f( 1.0f,-1.0f, 1.0f); // Bottom Right Of The Quad (Front)

GL.glColor3f(1.0f,1.0f,0.0f); // Set The Color To Yellow
GL.glVertex3f( 1.0f,-1.0f,-1.0f); // Bottom Left Of The Quad (Back)
GL.glVertex3f(-1.0f,-1.0f,-1.0f); // Bottom Right Of The Quad (Back)
GL.glVertex3f(-1.0f, 1.0f,-1.0f); // Top Right Of The Quad (Back)
GL.glVertex3f( 1.0f, 1.0f,-1.0f); // Top Left Of The Quad (Back)

GL.glColor3f(0.0f,0.0f,1.0f); // Set The Color To Blue
GL.glVertex3f(-1.0f, 1.0f, 1.0f); // Top Right Of The Quad (Left)
GL.glVertex3f(-1.0f, 1.0f,-1.0f); // Top Left Of The Quad (Left)
GL.glVertex3f(-1.0f,-1.0f,-1.0f); // Bottom Left Of The Quad (Left)
GL.glVertex3f(-1.0f,-1.0f, 1.0f); // Bottom Right Of The Quad (Left)

GL.glColor3f(1.0f,0.0f,1.0f); // Set The Color To Violet
GL.glVertex3f( 1.0f, 1.0f,-1.0f); // Top Right Of The Quad (Right)
GL.glVertex3f( 1.0f, 1.0f, 1.0f); // Top Left Of The Quad (Right)
GL.glVertex3f( 1.0f,-1.0f, 1.0f); // Bottom Left Of The Quad (Right)
GL.glVertex3f( 1.0f,-1.0f,-1.0f); // Bottom Right Of The Quad (Right)

GL.glEnd();

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godkane    122
Let me try to explain this again:
I'm trying to get glArrayElements and glDrawElements to work in C# and am having problems. I do not have lighting. Example 1 works like it should, well Example 2 shows a blank screen and Example 3 crashs.

float[,] vertices = {{ -1.0f, -1.0f, 1.0f},
{ 1.0f, -1.0f, 1.0f},
{ 1.0f, 1.0f, 1.0f},
{ -1.0f, 1.0f, 1.0f}};
private float[,] colors = {{1.0f, 0.0f, 1.0f },
{1.0f, 0.0f, 1.0f },
{1.0f, 0.0f, 1.0f },
{1.0f, 0.0f, 1.0f}};
byte[,] frontIndices = {{0, 1, 2, 3}};

GL.glEnableClientState(GL.GL_COLOR_ARRAY);
GL.glEnableClientState(GL.GL_VERTEX_ARRAY);
GL.glColorPointer(3, GL.GL_FLOAT, 0, colors);
GL.glVertexPointer(3, GL.GL_FLOAT, 0, vertices);

Example 1
GL.glColor3f(1.0f,0.0f,1.0f);
GL.glBegin(GL.GL_QUADS);
GL.glVertex3f(vertices[0,0], vertices[0,1], vertices[0,2]);
GL.glVertex3f(vertices[1,0], vertices[1,1], vertices[1,2]);
GL.glVertex3f(vertices[2,0], vertices[2,1], vertices[2,2]);
GL.glVertex3f(vertices[3,0], vertices[3,1], vertices[3,2]);
GL.glEnd();

Example 2
GL.glArrayElement(0);
GL.glArrayElement(1);
GL.glArrayElement(2);
GL.glArrayElement(3);

Example 3
GL.glDrawElements(GL.GL_QUADS, 4, GL.GL_BYTE, frontIndices);

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