Apparently GL_POINT_SPRITE is important to GL 3.2+ compatibility profile, not just to GL 2.1 as thought.
We'll remove this during the core profile transition.
At context startup, make sure our assumptions about the OpenGL version are true. Should match since we set up the contexts... but this is what asserts are for, to check "should"s!
Part of T49012
Complete (for our needs) 2D & 3D transformation API. Should be easy to port legacy OpenGL matrix stack-based code to this. Still needs testing.
Ported ortho, frustum, lookAt functions from Viewport FX (rB194998766c65). Kept plenty of Viewport FX code from previous commit.
Stack API and 2D routines ported from Gawain. This version uses BLI_math library so everything is licensed under GPL instead of the usual MPL.
Part of T49450
Ignore texture matrix in the shader, stop messing with texture matrix in BLF code.
Use linear screen-space interpolation instead of perspective.
Avoid redundant call to glMatrixMode.
With USE_GLSL enabled, GPU_basic_shader(TEXTURE|COLOR) always rendered black. New shader uses a solid color + alpha channel of texture (which in our case is a font glyph). See fragment shader for details.
I prefer this approah -- multiple shaders that each do one thing well (and are easy to read/write/understand), instead of one shader that can do many things given the right options.
Fixed compile error in debug build (thanks mont29)
Renamed some functions for consistency.
New features:
Create a Batch with immediate mode! Just use immBeginBatch instead of immBegin. You can keep the result and draw it as many times as you like. This partially replaces the need for display lists.
Copy a VertexFormat, and create a VertexBuffer using an existing format.
Resize a VertexBuffer to a different number of vertices. (can only resize BEFORE using it to draw)
Was already done for immediate mode, but rearranged code to make a clean separation. Cleaned up #includes for code that uses this feature.
Added same for batched rendering.
Follow-up to rBddb1d5648dbd
API is nearly complete but untested.
1) create batch with vertex buffer & optional index buffer
2) choose shader program
3) draw!
This function modifies the GL program object, which reduces our ability to share a shader among meshes with different vertex formats. Recommended approach is to use get_attrib_locations.
Vertex Buffer to store vertex attribute data.
Element List (AKA Index Buffer) to select which vertices to use.
Batch combines these into an object that can be built once then drawn
many times.
Porting over from the C++ version… Most of this C code is compiled but
unused. Some of it is not even compiled. Committing now in case I’m
lost at sea.
Put Gawain source code in a subfolder to make the boundary between the
library and the rest of Blender clear.
Changed Gawain’s license from Apache to Mozilla Public License. Has
more essence of copyleft — closer to GPL but not as restrictive.
Split immediate.c into several files so parts can be reused (adding
more files soon…)
immBegin requires us to know how many vertices will be drawn. Most times this is fine, but sometimes it can be tricky. Do we make the effort to count everything in one pass, then draw it in a second?
immBeginAtMost makes this simple. Example: I'll draw at most 100 vertices. Supply only 6 verts and it draws only 6.
Any unused space is reclaimed and given to the next immBegin.
Was using GL_NONE to mean "no primitive" but GL_NONE and GL_POINTS are both defined as 0x0000.
Introducing PRIM_NONE = 0xF which does not clash with any primitive types.
transparency.
The issue is that we are rendering to a 0..1 clamped sRGB buffer with
unpremultiplied alpha, where the correct thing to do would be to render
to an unclamped linear premultiplied alpha buffer. Then we would just
make fire purely emissive without affecting the alpha channel at all,
but that doesn't work here.
So for now, draw fire and smoke separately using different shaders and
blend modes, like it used to before the smoke programs were rewritten
(see rB0372b642).
Application code can pass ubytes, Gawain converts to float vec4 expected by shader.
For now the conversion is simple linear. We can add sRGB support later if needed.
Scanned Blender code for commonly used glVertex, glColor functions.
Implemented immVertex, immAttrib versions of these to ease transition
away from legacy OpenGL.
Errors are caught & reported by our GL debug callback. This gives us way more useful information than sporadic calls to glGetError.
I removed almost all use of glGetError, including our own GPU_ASSERT_NO_GL_ERRORS and GPU_CHECK_ERRORS_AROUND macros.
Still used in rna_Image_gl_load because it passes unvalidated input to OpenGL functions.
Still used in gpu_state_print_fl_ex as an exception handling hack -- will rewrite this soon.
The optimism embodied by this commit will not prevent OpenGL errors. We need to analyze what would cause GL to fail at certain points and proactively intercept these failures. Or guarantee they can't happen.
Legacy OpenGL has a matching Vertex3fv for every Vertex3f, and so on. Add something similar to Gawain, just for a few common functions. Might add more as the need arises.
